src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetC1_x86.cpp

rev 55609 : Eliminate extra forwarding pointer per object

*** 34,43 ****
--- 34,44 ----
    Register addr = _addr->as_register_lo();
    Register newval = _new_value->as_register();
    Register cmpval = _cmp_value->as_register();
    Register tmp1 = _tmp1->as_register();
    Register tmp2 = _tmp2->as_register();
+   Register tmp3 = _tmp3->as_register();
    Register result = result_opr()->as_register();
    assert(cmpval == rax, "wrong register");
    assert(newval != NULL, "new val must be register");
    assert(cmpval != newval, "cmp and new values must be in different registers");
    assert(cmpval != addr, "cmp and addr must be in different registers");
*** 51,61 ****
      __ mov(rscratch1, newval);
      __ encode_heap_oop(rscratch1);
      newval = rscratch1;
    }
  
!   ShenandoahBarrierSet::assembler()->cmpxchg_oop(masm->masm(), result, Address(addr, 0), cmpval, newval, false, tmp1, tmp2);
  }
  
  #undef __
  
  #ifdef ASSERT
--- 52,62 ----
      __ mov(rscratch1, newval);
      __ encode_heap_oop(rscratch1);
      newval = rscratch1;
    }
  
!   ShenandoahBarrierSet::assembler()->cmpxchg_oop(masm->masm(), result, Address(addr, 0), cmpval, newval, false, tmp1, tmp2, tmp3);
  }
  
  #undef __
  
  #ifdef ASSERT
*** 76,89 ****
        cmp_value.load_item_force(FrameMap::rax_oop_opr);
        new_value.load_item();
  
        LIR_Opr t1 = gen->new_register(T_OBJECT);
        LIR_Opr t2 = gen->new_register(T_OBJECT);
        LIR_Opr addr = access.resolved_addr()->as_address_ptr()->base();
        LIR_Opr result = gen->new_register(T_INT);
  
!       __ append(new LIR_OpShenandoahCompareAndSwap(addr, cmp_value.result(), new_value.result(), t1, t2, result));
        return result;
      }
    }
    return BarrierSetC1::atomic_cmpxchg_at_resolved(access, cmp_value, new_value);
  }
--- 77,91 ----
        cmp_value.load_item_force(FrameMap::rax_oop_opr);
        new_value.load_item();
  
        LIR_Opr t1 = gen->new_register(T_OBJECT);
        LIR_Opr t2 = gen->new_register(T_OBJECT);
+       LIR_Opr t3 = gen->new_register(T_OBJECT);
        LIR_Opr addr = access.resolved_addr()->as_address_ptr()->base();
        LIR_Opr result = gen->new_register(T_INT);
  
!       __ append(new LIR_OpShenandoahCompareAndSwap(addr, cmp_value.result(), new_value.result(), t1, t2, t3, result));
        return result;
      }
    }
    return BarrierSetC1::atomic_cmpxchg_at_resolved(access, cmp_value, new_value);
  }